3. Electroplating The electroplating method is more professional. For those bag hardware that are severely worn and have an electroplated layer, you can try to use electroplating to restore the original luster of the bag hardware. Methods to prevent and solve chain discoloration: Apply it with transparent nail polish, or use a thin layer of nail polish, and it is best to apply it as soon as you buy it to prevent fading. Because applying nail polish to the surface of a metal chain is equivalent to adding a protective film to the metal chain, which not only prevents direct friction of clothing on the chain, but also prevents sulfides in the air from corroding the plated layer. After using it for a period of time, nail polish needs to be reapplied, especially in areas with frequent contact and friction. Spray the chain with varnish to prevent oxidation. If it’s a gold chain, you can recolor it with a gold paint pen. If the discoloration is too severe, you can replace the chain.